Spinal Epidural Abscess

Audience The aim of this simulation case is to educate senior medical students, resident physicians, and advanced practice providers on the recognition, diagnosis, and management of spinal epidural abscesses. This scenario is most applicable to the emergency medicine setting but can be applied to the outpatient office or urgent care settings. Introduction Spinal epidural abscess is an infection leading to an epidural collection of purulent material. This uncommon condition is estimated to occur less than 12 times per 100,000 hospital admissions.1,2 However, this infection can lead to devastating neurological sequelae via cord compression, spinal vascular interruption, and inflammatory etiologies;3,4 thus, prompt diagnosis is essential. Unfortunately, spinal epidural abscesses may be difficult to identify clinically due to variable clinical presentations. The goal of this scenario is to increase awareness of this critical diagnosis. Detailed history-taking to identify risk factors will aid in the recognition of spinal epidural abscesses. Many of the risk factors are related to increased infectious risk from hematogenous spread, iatrogenic inoculation, or direct extension.1 Individuals with conditions including intravenous (IV) drug use, alcohol abuse, diabetes, human immunodeficiency virus (HIV), cancer, hepatic disease, renal disease, and other immunocompromising conditions are at increased risk of developing epidural abscesses.1 Primary infectious sources include dental abscesses, endocarditis, vertebral osteomyelitis, and soft tissue infections. Spinal procedures including spinal surgeries, paraspinal injections, and placement of epidural catheters or stimulators can also predispose to infection.2,4 Classic symptoms for spinal epidural abscesses include fever, back pain and neurological changes.1,5 Back pain is the most frequent presenting symptom, occurring about 70%–90% of the time.1 However, fever is the least frequent presenting symptom4 and neurological findings only occur in about one-third of cases.2 Neurological symptoms include motor weakness, sensory changes, urinary retention, overflow urinary incontinence, bowel dysfunction, hyperreflexia, radicular pain, spinal shock or cauda equina syndrome.1,4 Laboratory findings may include systemic leukocytosis and elevated inflammatory markers. Whereas leukocytosis is estimated to be present in two-thirds of cases,2 Davis, et al. showed that with the concurrent presence of a risk factor, an elevated erythrocyte sedimentation rate (ESR) had 100% sensitivity and 67% specificity for spinal epidural abscesses.5 Magnetic resonance imaging (MRI) with gadolinium contrast is the preferred imaging modality for diagnosing spinal epidural abscesses. Computed tomography (CT) with myelography can be considered if MRI is contraindicated.1 Given that abscesses may be multifocal, further spinal imaging beyond a single spinal segment should be considered during evaluation. Lumbar puncture is not recommended due to risk of iatrogenic infectious spread. Treatment of epidural abscesses includes obtaining blood cultures and prompt antibiotic administration with early surgical evaluation to determine if operative intervention is warranted. Staphylococcus aureus is the most common microbial cause, contributing to about two-thirds of cases.3,4 Other microbial causes include coagulase-negative Staphylococcus (ie, Staphylococcus epidermidis), Streptococcus, gram-negative bacilli (ie, Pseudomonas aeruginosa and E. coli), and less commonly, anaerobic bacteria, fungi, mycobacteria and parasites.1,2 Empiric antibiotic treatments generally include vancomycin and a third- or fourth- generation cephalosporin.2,4 This simulation session will highlight the importance of recognizing and aggressively treating this uncommon but potentially devastating condition. Educational Objectives After this simulation case, learners will be able to diagnose and manage patients with spinal epidural abscesses. Specifically, learners will be able to: Obtain a detailed history, including past infectious, surgical, procedural and social history to evaluate for epidural abscess risk factors. Describe clinical signs and symptoms of spinal epidural abscesses and understand that initial clinical presentations can be variable. Perform a focused neurological exam including evaluation of motor, sensory, reflexes, and rectal tone. Order appropriate laboratory testing and imaging modalities for spinal epidural abscess diagnosis, including a post-void bladder residual volume. Select appropriate antibiotics for empiric treatment of spinal epidural abscess depending on patient presentation. Disposition the patient to appropriate inpatient care. Educational Methods The authors conducted this simulation case with a standardized patient. We encourage inclusion of a standardized patient versus a mannequin to provide appropriate motor and sensory exams. For those without a standardized patient program, the authors suggest utilizing a faculty member as the patient. Regardless of individual used, it is strongly recommended that facilitators rehearse the case with the individual in the patient role ahead of time in order to ensure that their performance reflects an accurate neurologic exam. A debriefing session and small-group discussion followed the simulation to review the clinical presentation, diagnosis, management, and treatment of spinal epidural abscesses. This case can also be adapted as an oral boards case. Research Methods Residents were provided a survey at the completion of the debriefing session to rate different aspects of the simulation, as well as to provide qualitative feedback on the scenario. This survey is specific to our institution’s simulation center. Results While qualitative feedback from the residents was positive, it was viewed as a straightforward case. Our initial presenting symptom was difficulty ambulating with a fever at home, if asked. The residents appreciated performing a neurologic exam on a standardized patient versus attempting this on a mannequin. Our simulation center’s feedback form is based on the Center of Medical Simulation’s Debriefing Assessment for Simulation in Healthcare (DASH) Student Version Short Form with the inclusion of required qualitative feedback if an element was scored less than a 6 or 7. This session received all 7 scores (extremely effective/outstanding) other than one 5 score for the element assessing if the instructor set the stage for an engaging learning experience. The learner’s feedback for this 5 score was “kinda went right into the case which was ok.” Our form also includes an area for general feedback about the case at the end. Comments included “Great sim. Expert case writing,” “Fun case and learned a lot,” and “Great case! Appreciated feedback on consulting and the difficult consultant situation.” Discussion This is a cost-effective method for reviewing epidural abscess. We chose a chief complaint and history that was slightly atypical from “classic” presentations, but not so esoteric that the residents felt cheated at the end of the scenario. When using a standardized patient in a scenario that may involve a sensitive physical exam, we review with learners and the standardized patient what expectations are during the pre-brief session. For example, residents may say, “we would like to check to see if rectal tone is intact,” and then the standardized patient would verbalize back the expected physical exam findings. Topics Medical simulation, spinal epidural abscess, spinal cord compression, infectious disease.

leukocytosis is estimated to be present in two-thirds of cases, 2 Davis, et al. showed that with the concurrent presence of a risk factor, an elevated erythrocyte sedimentation rate (ESR) had 100% sensitivity and 67% specificity for spinal epidural abscesses. 5gnetic resonance imaging (MRI) with gadolinium contrast is the preferred imaging modality for diagnosing spinal epidural abscesses.Computed tomography (CT) with myelography can be considered if MRI is contraindicated. 1 Given that abscesses may be multifocal, further spinal imaging beyond a single spinal segment should be considered during evaluation.Lumbar puncture is not recommended due to risk of iatrogenic infectious spread.
Treatment of epidural abscesses includes obtaining blood cultures and prompt antibiotic administration with early surgical evaluation to determine if operative intervention is warranted.Staphylococcus aureus is the most common microbial cause, contributing to about two-thirds of cases. 3,4Other microbial causes include coagulase-negative Staphylococcus (ie, Staphylococcus epidermidis), Streptococcus, gram-negative bacilli (ie, Pseudomonas aeruginosa and E. coli), and less commonly, anaerobic bacteria, fungi, mycobacteria and parasites. 1,2Empiric antibiotic treatments generally include vancomycin and a third-or fourth-generation cephalosporin. 2,4is simulation session will highlight the importance of recognizing and aggressively treating this uncommon but potentially devastating condition.
Educational Objectives: After this simulation case, learners will be able to diagnose and manage patients with spinal epidural abscesses.Specifically, learners will be able to: 1. Obtain a detailed history, including past infectious, surgical, procedural and social history to evaluate for epidural abscess risk factors.Describe clinical signs and symptoms of spinal epidural abscesses and understand that initial clinical presentations can be variable.2. Perform a focused neurological exam including evaluation of motor, sensory, reflexes, and rectal tone.3. Order appropriate laboratory testing and imaging modalities for spinal epidural abscess diagnosis, including a post-void bladder residual volume.4. Select appropriate antibiotics for empiric treatment of spinal epidural abscess depending on patient presentation.5. Disposition the patient to appropriate inpatient care.
Educational Methods: The authors conducted this simulation case with a standardized patient.We encourage inclusion of a standardized patient versus a mannequin to provide appropriate motor and sensory exams.For those without a standardized patient program, the authors suggest utilizing a faculty member as the patient.Regardless of individual used, it is strongly recommended that facilitators rehearse the case with the individual in the patient role ahead of time in order to ensure that their performance reflects an accurate neurologic exam.A debriefing session and small-group discussion followed the simulation to review the clinical presentation, diagnosis, management, and treatment of spinal epidural abscesses.This case can also be adapted as an oral boards case.
Research Methods: Residents were provided a survey at the completion of the debriefing session to rate different aspects of the simulation, as well as to provide qualitative feedback on the scenario.This survey is specific to our institution's simulation center.
Results: While qualitative feedback from the residents was positive, it was viewed as a straightforward case.Our initial presenting symptom was difficulty ambulating with a fever at home, if asked.The residents appreciated performing a neurologic exam on a standardized patient versus attempting this on a mannequin.
Our simulation center's feedback form is based on the Center of Medical Simulation's Debriefing Assessment for Simulation in Healthcare (DASH) Student Version Short Form with the inclusion of required qualitative feedback if an element was scored less than a 6 or 7.This session received all 7 scores (extremely effective/outstanding) other than one 5 score for the element assessing if the instructor set the stage for an engaging learning experience.The learner's feedback for this 5 score was "kinda went right into the case which was ok."Our form also includes an area for general feedback about the case at the end.Comments included "Great sim.Expert case writing," "Fun case and learned a lot," and "Great case!Appreciated feedback on consulting and the difficult consultant situation."

Objectives:
After this simulation case, learners will be able to diagnose and manage patients with spinal epidural abscesses.Specifically, learners will be able to: 1. Obtain a detailed history, including past infectious, surgical, procedural and social history to evaluate for epidural abscess risk factors.

Equipment or Props Needed:
Upper extremity moulage consistent with track marks For lower-cost utilization, can use makeup and a small damp makeup brush to apply faint dark red color in small spots in a linear fashion or in a cluster over the patient's natural upper extremity vasculature.Cardiac monitor Pulse oximetry Temperature probe Angiocatheters for peripheral intravenous access (18 to 22 gauge) Intravenous (IV) pole Ultrasound for bladder volume assessment Simulated medications with labeling: acetaminophen, vancomycin, ceftriaxone, hydromorphone, morphine

Confederates needed:
Patient and primary nurse.Facilitators running the simulation may call in as orthopaedic or neurosurgical consultants and the hospitalist.

Initial presentation:
Patient is a 45-year-old female with history of type 1 diabetes mellitus who presents via EMS from home with urinary retention and fatigue.Patient is lying on left side, tearful, and able to converse.Patient reports history of chronic pain and asks repeatedly for pain medication.

How the scenario unfolds:
Patient is a 45-year-old female who presents via EMS from home with urinary retention, fatigue, and generalized pain.Participants should perform a physical exam to identify signs of IV drug use and neurological deficits.A post-void residual bladder volume should be obtained, showing urinary retention.The participants should order blood work for infectious workup, initiate antibiotics, and obtain an emergent spinal MRI showing spinal epidural abscess.If antibiotics are not initiated by the 9-minute mark, patient will begin to have progressively worsening tachycardia, hypotension, and will develop a fever.If participants attempt to discharge patient during scenario, patient will be unable to safely ambulate.

Critical actions:
1. Perform back exam, including palpation of the entire spine and direct visual inspection.-If asked, there has been a fever up to 100.8°F intermittently for the past three days.
-If asked, you cannot fully empty your bladder despite the need to do so and you are now urinating small amounts on yourself when you cough or sneeze.
Past medical history -Type 1 diabetes, for which you take sliding scale insulin.
-No previous surgeries.
-You are not allergic to anything.
-If they initially ask about alcohol, smoking, or drugs, you will initially refuse to answer, saying "I don't see how that is important right now.Can't you see if I'm in pain?" o If learners then explain why they are asking social history questions, you will confirm that you drink 2-3 alcoholic drinks a week and smoke tobacco cigarettes.o If they ask about intravenous drug use, shrug and nod affirmatively, but when asked details, mention again that your back pain really hurts right now.
-Various family members (if asked, your maternal grandparents) have had type 2 diabetes.
Physical exam -Your midback and low back will significantly hurt, even if they press lightly.Any movement will make you grimace in pain.-When they press over your lower central abdomen (2/3 up to your umbilicus/belly button from your pubic bone in the front), you'll say "Careful, that makes me feel like I have to pee." -Your strength is normal in your arms.
-If they ask about your track marks, say "oh, that's from my insulin.

Symptoms/Findings
The diagnosis of epidural abscess is difficult due to lack of disease-defining symptoms or clinical findings.Epidural abscesses are classically associated with fever, back pain, and neurological deficits; however, patients seldomly present with all these symptoms. 2,5Some patients may not initially present with fever. 4Thus, awareness and suspicion for this diagnosis is necessary.Practitioners should consider obtaining complete blood count to evaluate for leukocytosis and ordering inflammatory markers.Unfortunately, leukocytosis is only found in about two-thirds of spinal epidural abscess cases and elevations of ESR or CRP are not specific for this diagnosis. 2

Diagnosis
The imaging modality of choice for diagnosis is MRI with contrast. 2Consider imaging multiple areas of the spinal cord given the epidural abscess may extend further than one spinal segment or may involve multiple spinal segments. 4Lumbar puncture is not recommended due to risk of infectious spread if the abscess is accessed during the procedure. 4

Other debriefing points
• What imaging modalities would learners pursue if the patient was unable to obtain an MRI due to an incompatible pacemaker or retained metal?• How did you address analgesia in this patient?
• Tell me about your neurologic exam.Now knowing the diagnosis, would you have performed this neurologic exam differently?

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History of present illness: Patient is a 45-year-old female who presents via EMS from home.She has had fatigue for two days.If asked specifically, she feels like she can't fully empty her bladder despite the need to do so and she often urinates small amounts on herself whenever she coughs or sneezes.Patient appears distressed, tearful, and repeatedly reports chronic 10/10 generalized pain.Patient called EMS today because she could not get out of bed.Denies falls, trauma, or recent diarrhea.•Past medical history: Type 1 diabetes mellitus • Past surgical history: No prior surgeries • Medications: Insulin • Allergies: None • Social history: When initially asked about alcohol, smoking, or drugs, patient refuses to answer, saying "I don't see how that is important right now.Can't you see I'm in pain?"If learners then explain why they are asking social history questions, the patient will admit to 2-3 alcoholic drinks a week, smoking tobacco cigarettes, and will shrug and nod affirmatively if asked about intravenous drug use (but still will not divulge further details regarding this).• Family history: Type 2 diabetes (maternal grandparents) Secondary Survey/Physical Examination: INSTRUCTOR MATERIALS eturn: Calibri Size 10 Luo CT, et al.Spinal Epidural Abscess.JETem 2020.5(1):S26-52.https://doi.org/10.21980/J8T93835 General appearance: Patient is lying on her left side.She appears distressed and tearful.She repeatedly asks for pain medication.Patient is otherwise able to converse appropriately.• HEENT: o Head: within normal limits o Eyes: within normal limits o Ears: within normal limits o Nose: within normal limits o Throat: within normal limits • Neck: within normal limits • Heart: Normal rate and rhythm, no murmurs • Lungs: Clear lung sounds • Abdominal/GI: Suprapubic discomfort upon palpation without guarding, rebound, or rigidity • Genitourinary: Palpable bladder appreciated extending caudally 2/3 up to the umbilicus • Rectal: (verbalized by the standardized patient): Decreased rectal tone and decreased perianal sensation • Extremities: Track marks noted diffusely over the bilateral upper extremities without superimposed cellulitis • Back: No skin changes or deformities noted other than upper extremity track marks as above.Diffuse tenderness over the lower lumbar spine.No costovertebral angle tenderness.• Neuro: Glasgow coma scale (GCS) 15 (eyes 4, verbal 5, motor 6).Cranial nerves intact.5/5 symmetric upper extremity motor strength with shoulder shrug, elbow flexion and extension, wrist flexion, wrist extension, anterior interosseus muscles (AIN), posterior interosseous muscles (PIN), and intrinsics.5/5 hip flexion bilaterally.3/5 motor strength with knee flexion, knee extension, plantar flexion, dorsiflexion, and extensor hallucis longus bilaterally.Sensation is intact over upper extremity dermatomes bilaterally.Decreased sensation diffusely over bilateral lower extremities, but particularly decreased in the L4 distribution from the anterior knee and extending medially and distally to the medial malleolus.Symmetric 1+ patellar and Achilles reflexes.Intact finger-to-nose testing bilaterally.Heel-to-shin maneuvers unable to be completed due to lower extremity weakness.• Skin: Track marks over bilateral upper extremities, as above • Lymph: within normal limits • Psych: Anxious, denies suicidal ideation

Case Title: Spinal Epidural Abscess Case Description & Diagnosis (short synopsis): Patient
with a spinal epidural abscess.Appropriate antibiotics and pain medication should be ordered and patient case discussed with spinal surgery consultant.Patient should ultimately be admitted to inpatient care.
Now you have to hold on to things to get around or hold on to someone for support.o Normally ambulates without any problems.o If asked, you have not had diarrhea recently.-Normally has chronic back pain "all over" and you're not sure if it is worse today."It's always a 10/10."o Takes tramadol, ibuprofen, and acetaminophen as needed for pain.
" -In your legs, you can weakly do what they ask (lift your leg, bend your knee, straighten your knee, toes up, toes down, big toe up) if it is against gravity, or when you're lying on your side without them putting any pressure on your legs for resistance.Start crying and ask "what's wrong with my legs?" -If they ask you to stand up or walk, you will almost fall while getting out of bed to stand and have to be steadied by the nurse.oIf learners ask if you have trouble walking/moving your legs due to weakness or pain, become tearful and say "Both!My back always hurts, but my legs just aren't working right."oIf they ask about sensation in your legs, it'll be less than normal everywhere, but almost completely numb over the middle of your kneecaps, the middle lower legs, and your inner ankles bilaterally.-Ifthe learners ask about rectal tone, you can verbalize "Rectal tone is intact."Workup-If the learners order a foley catheter, say "Whoa, why are you ordering that?"Then agree to have it placed once learners explain why it is needed.-If the learners discharge you, you will almost fall while getting out of bed to stand and have to be steadied by the nurse.You will then say "How can I go home when I can't walk?!" -If the learners do not explain what is going on after the MRI test, ask them "what did the tests show?" eturn: Calibri Size 10 Luo CT, et al.Spinal Epidural Abscess.JETem 2020.5(1):S26-52.https://doi.org/10.21980/J8T93846

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What would you do if the patient became tearful and asked if they did this to themselves due to the intravenous drug use?What about if the patient wishes to leave against medical advice?• Ensure that closed-loop communication was used between team members.Reflect on whether closed-loop communication occurred.Discuss why it was or was not used.Discuss how use or lack of closed-loop communication affected outcomes during the case.